Transcript Electromagnetic Spectrum

Electromagnetic Spectrum
Electromagnetic Spectrum
• Electromagnetic Spectrum- Wide range of
electromagnetic waves with different
frequencies and wavelengths and divided
into parts
– All waves travel at the same speed in empty
space
Electromagnetic Spectrum
Radio Waves
• Radio Waves- Lowest frequency of all electromagnetic
waves and carry the least energy
– Ex: TV, AM/FM
• Antennas vibrate to send or receive radio waves
• Microwaves are used to heat food and transmit calls on
cell phones
• Radar uses electromagnetic waves to detect objects like
echolocation
Infrared Waves
• Infrared WavesElectromagnetic
waves that emit heat.
• Infrared detectors
detect objects that are
warmer and cooler
than their
surroundings
– Ex: Pit vipers use
infrared to detect prey
Visible Light
• Visible Light- Electromagnetic waves that you
can see with your eyes
– Different wavelengths have different colors
– Red light (longest wavelength) and blue light (shortest
wavelength)
• Most objects don’t emit light; they reflect light
Ultraviolet Radiation
• Has higher frequency than
visible light and even shorter
wavelengths
• Carries more energy and can
damage large molecules and
kill cells
• Ex: Sunburn
• Benefits- Vitamin D is able to
be produced and disinfect
equipment to sterilize
• Ozone layer absorbs some of
the UV rays
X Rays and Gamma Rays
• X rays have higher frequency
than UV rays and can go
through skin and muscle
• Gamma rays have highest
frequency and carry the most
energy
– Produced by changes in the
nuclei of atoms
• X rays and gamma rays can
damage and kill cells
• Gamma rays are used to kill
cancer and bacteria